Ever accepted a job without negotiating?

I just wanna rant about this somehwere because I honestly dont know what I to do.

TLDR: ADHD/AuDHD folks - have you ever accepted an offer without negotiating because of burtnout and felt awful later?

So I recently got this FT offer and I didnt even apply for it. I had applied for a casual position but they came back and offered me this one instead. At that time, I was going through a lot mentally and emtoionally. Because I was involved in aother project we were trying to spin out as a startup. There were constant conflicts, ambiguity and I barely ate, slept or did anything other than staying afloat. When the offer came in, I completely forgot to even talk about the pay. So I just accepted it. Then right before the day I started, I looked into the position details and the pay scale. On my first day, I brought it up with my lead ad recruiter. they directed me to my manager. I only asked if there was space to have discussion about it or if it was osmehting I could bring up during my performance review. Now after talking to my collegues (who were all hired at the same time as me) I found out they all negotiated their pay. And their difference betweem their rate and mine is around $7 - 9 per hour. It honestly upsets me so much.

I know i would have spoken up if I had been in a better headspace back then. I am trying to put it behind me and be grateful for the opportunity. I cant help but feel like its unfair. But I am also wondering is this something other ADHD/AuDHD people have experienced and how they worked around this?